Ok, it's not working because you are trying to use the server certificate on a client. Each certificate is marked as server or as client. By default, there's only one certificate in the certificate-manager which the one used on the server side. You need to generate a new certificate, choose a unique CN, an optionnal IP and comment, then, let the type to 'client'. Now configure your client with this new certificate. When you click on the link 'display' of a client certificate, you'll have the correct configuration file, it doesn't work for servers' certificate, that's why you get the message "Configuration file are only generated for client certificate, not server"